Safety-crank for explosive-engines.



J. 1). BOWNE. SAFETY CRANK FOR EXPLOSIVE ENGINES.

APPLIOATIONTILED AUG. 18, 1910.

Patented July 4, 1911;

V 1 avwewfoz q vitmeaaca aw 0 W w ("1 How m JOHN D. Bownn, or new roan,

N. Y., ASSIGNOR or ONE-HALF TO SAMUEL L. BEVAN, or new YORK, N. Y.

SAFETY-CRAN r03 nxrtosrvn-nnernns Specification of Letters Patent.

Patented July 4, 191 1.

1 Application filed August 18, 1910. Serial No. 577,762.

.Td all whom it concern:

-.Be it known that I, J 0H1: D. BOWNE, citizen of-the United States,residing at New York, in the county of New York and State of New York,have invented certain new.

and useful Improvements in Safety-Cranks for Explosive-Engines, ofwhich; the following is a specification. I This invention relatestosafety cranks for ezgplosive engines, particularly to those dev viceswhereln a sprlng or springs is interposed to cushion the elfect upon theperson operating the crank of a premature or back fire explosion.

special arrangement a and whereby it is believed the disengagement ofthe crank from the shaft is brought about in the shortest period oftime, and thefshock of back fire of the engine is to a great extenttaken up and the hand and arm of the operator correspondingly relievedand'practically guarded from in ury.

The construction and arrangement of parts comprising this inventionappear in the accompanying drawings, of which- Figure 1 represents aside view ofallthe parts separated from each other upon the shaft, andabout to be assembled. Fig. 2 is a front view of all parts assembled,and Fig. '3 is a side view of the parts assembled, some of them beingshownin longitudinal section.

The same letter is employed to refer to the same part throughout thedescription and drawings.

. Upon the shaft A, the ratchet crown is" fixed by means of pin b. Theouter ring ofv ratchet teeth are designated by the letter C,

and there willbe noted, as best shown in Fig. 1, an inner ring ofratchet teeth D, that project beyond the teeth 0.

The shell E fits movably upon the fixed crown B. The shell E has aseries of ratchet teeth eat the rear, and a pair of slots F and F, theslot F being diametrically opposite the similar-slot F. The shell E is.adapted to receive also the ratchet ring G, the teeth of. which arereferred to by the letter 9.

, Projecting from the outside of the ring Gr,

and, formed integrally with the ring, are

the arInH and lug 11., located at opposite points. -When the parts areassembled, and

thering G is passed into the shell E, the lug k and'arm entertherecesses fand ffg'by,

way of which the lug and arm reach the slots F and F which it isintended they shall traverse.

In Fig. 1 the shell E is illustrated wall only of each of the recesses fand f are insec-i tron lengthwise of the shaft and one side.

shown. Let it"be now assumed that the ring I G has been passed'intotheshell E, and that the. lug h and. arm H have passed through therecesses or openings f and f into the slots F and F. It is thought to beclear that the ring may now be'rotated partly and outer member oi coverJ is slipped over the recessed end of the shell E, and covers the lughas bestshown in Fig. 3. The arm H does not interfere with the placing ofthe.

already mentionedas features of the fixed crown B correspond in size andnumber with the teeth is. On the exterior, the cover J is provided withthe ratchet-toothed center or hub M, the teeth of which, and of the bossN of the crank O are alike and are arranged to be brought intoengagement when the crank is operated. The teeth on the crank boss aredesignated by the letter 7.

The supporting plate P, shown in Figs. 2 and 3, lies against the fixedcrown B, and

the lug and arm will travel the slots. The ring and shell beingnowassociated, the The object of this invention is the-production of asafety crank havingip'art's of construction, 3

the shaft passesmovably through the'plate which, in practice, isfastened to the ve'- .hicle. Upon the plate P, as shown in Fig. 3,

is a pivoted pawl Q engaging the ratchet.

teeth 6 of shell E, and which will be again mentioned. In Figs. 2' and 3it will be also noted that the arm H of ring G is pivotally connectedwith the plunger R, and that the head of the plunger bears against thecoil spring r, whic h may be compressed. by

means of the screw S and the adjusting disk T, engaging the screw withinthe dash-pot I] that contains the spring and lunger head- To explain theoperationof t is invent on,- let it be assumed that the crank is engagedas shown in Fig. 3,'whereupon all the parts, excepting the fixed crow'nB and those borne byplat'e P may be moved togethertoward the plate untilthe teeth D, and k are partly engaged as shown. Now, the assoclated- 25jerk uponthe hand.' As

parts would .be halted were not the latch V raised out of the space,between the annular row of ratchet teeth a and the surface of the plateP. The latch V being thus raised, the

- teeth C of .the fixed crown B in engagement with the teeth 9 of ringG. The teeth D and is are now fully enmeshed. Under 10 thoseconditions,it isthought' to be" apparent that: the shaft may be turned.

Should therebe a, premature explosion having the effect of starting theengine re-- 'versely, the engagement of the pawl Q and ratchet teeth 0halts the shell'E, and the I dashpot U which :is attached as shown to athe shell; But, the ring.G having arm H receives the reverse impulsemomentarily,

which effect or shock-would be transmitted 2 to the hand holding thecrankdid not the) ie, and the inclined sides of the inner teeth D and 7care pressed together with the result that the parts move along theshaft, that is vto say, the shell E,rin'g G, cover J, and crank O, areall forced almost instantly to- 5 ward the right, thereby disengagingthe teeth, G and G InwF' resulting from back-fire has proceededfarc'lenough to release the ratchet teeth 0 an 9, 40 teeth lo and theconsequent movement to the right of the parts stated will continue untilteeth and 7a are free from each other. But, the movement at the point ofthe illustration in Fig. 3 has been suflicient to bring the ratchetteeth e away from plate P far enough to permit the latch V to fall intothe space bet-ween the teeth and the plate, and, the inadvertentreengagement of teeth may now continue its backward revolution withoutaifectingthe hand of the operator. Itis believed to be clear from thedrawings, that when the engine starts Jproper direction, in thisinstance ratchet teeth M and n are pressed together with the resultingdisengagement of the crank O in the customary manner.

in what I claim and desire to secure by Letters Patent is 1- with the1.. In a safety crank, the combination with a stationary plate having aof a shaft passing through the fixed to the shaft next to'the pivotedpawl, plate, a crown plate and havbest illustrated in' 1g. 3, theoperation but the teeth D still bear against the.

.O and g is. in that way prevented. The shaft up in the pot connectedand internally, the said ands of a watch, the inclined sides of the -hing an outer'and tlli finl'iel series of ratchet teeth, a shellconstructed to fit the crown movably, the said shell havteeth"arrangedto externally and ing a series of ratchet be brought intoengagement withthe pawl of said plate, the said-shell hawngopositely disposed.circumferential slots, a ashwith said shell and having within i'tanadjustable spring and a plum ger bearing againstthe said spring, a ringhaving ratchet teeth constructed to en a e the said outer series ofratchet teeth of said crown, the said ring armarranged to travel thesaid slots of the shell, the said arm of the ring being connectedi'ivotally with the. da'slF-pot, a .cover constructed to be secured saidplunger of the i having a lug and an externally to the shell and havingan internal' cylindrical portion constructed to fit the said ringmovably and internally, the said cylindrical portion havlng teeth.constructed to engage the inner series of -teeth of said crown,.the saidcover having-also an external central portion provided with .ratchetteeth, and a crank constructed with ratchet teeth fashioned to engagethe teeth of the said external central portion of the cover.-

' 2. In a safety a stationary plate having a a; shaft passing throughthe plates, a crown fixed to the shaft next to the plate and having anouter and an inner. series of ratchet crank, the combination withpivotal pawl, of

f teeth, ajshell constructed to fit the crown externally and movably,the said shell having a series of ratchet teeth arranged to be broughtinto engagement with the pawl .of said plate, the said shell havingoppositely disposed circumferential slots, means for latching the shellit an adjustable spring and a plunger bearing against the said spring,'a ring having ratchet teeth con structed to engage the said outerseries of ratchet teeth. having a lug and an arm arranged to travel thesaid {slots of the shell, the said arm of the ring being connectedpivotally with the said plunger of the dash-pot,"a cover constructed tobesecured externally to the shell and having an internal cylindricalportion constructed to fit the said ring movably cylindrical portionaving teeth constructed to engage the inner series of teeth of saidcrown, the said cover aving also an external centralportion pro.-

. vided with ratchet teeth, and a crank con now described thisinvention',-

structed with ratchet teeth fashioned to engage the teeth of the saidexternal central portion of the cover.

3. Ina safety crank, a stationary plate having a pivoted pawl, of ashaft passing through the plate,a crown .at a distance from the plate, adash-pot connected with said shell; and having within of said crown, thesaid ring the combinationwith fixed to' the shaft nextto the plate andhav- 7 ing a series constructed toengage e96,oos

ing an outer and an inner series of ratchet teeth, a shell constructedto fit the crown externally andmovably, the said shell havof ratchetteeth arranged to be brought into engagement with the pawl of the plate,the said shell having a circumferential slot, a ring having ratchetteeth the said outer series of ratchet teeth of said crown, the saidring having an arm arranged to travel the slot in said shell, meansincluding a spring for cushioning the movement of the ring with respectto the shell and connected with the arm of said ring and with the shell,a cover constructed to be secured externally to the shell and having aninternal cylindrical portion constructed to fit the said ring interiorlyand movably, the said cylindrical portion having teeth constructed toengage the said inner series of teeth of said crown, the said coverhaving also an external central portion provided with ratchet teeth, anda crank constructed with ratchet teeth fashioned. to engage the teeth ofthe said external central portion ofsaid cove 4:. In a safety crank, thecombination with a stationary plate having a pivoted pawl, of a shaftpassing through the plate, a crown fixed to the shaft next to the plateand having an-outer and an inner series of ratchet teeth, a shellconstructed to fit the crown ex- Copies of this patent may be obtainedfor five cents each, by addressing the ternally and movably, the saidshell having a series of ratchet teeth arranged to be brought intoengagement with the pawl of said plate, meansfor latching the shell at adistance from the plate, the said'shell having a circumferential slot, aring having ratchet teeth constructed to engage the said outer series ofratchet teeth of said crown, the said ring having an arm arranged totravel the slot in said shell, means including a spring for cushioningthe movement of the ring with respect to the shell and connected withthe arm of said ring and with the shell, a cover constructed to besecured externally to the shelland having an internal cylindricalportion constructed to fit the said ring interiorly and movably, thesaid cylindrical portion having teeth constructed to engage the saidinner series of teeth of said crown, the said cover having also anexternal central portion provided with ratchet teeth, and a crankconstructed with ratchet teeth fash ioned to engage the-teeth of thesaid external central portion of said cover.

In testimony whereof I afiix my signature in presence of two witnesses.

JOHN BOWNE.

' Witnesses:

GEORGE E. Monnow, FREDERICK GADE.

Commissioner of Patents,

